The introduction of new links to network topology could potentially contribute to greater capability to withstand system breakdowns. This paper analyzes the value of adding new cross-radial links for public transport network robustness. The value is evaluated in terms of passenger welfare under disruptions. Using a model that considers passengers' dynamic travel choices, stochastic traffic conditions, timetables and capacity constraints, a new light rail transit line in Stockholm, Sweden is evaluated. The results show that: (1) the cross-radial link reduces the impacts of disruptions of critical links; and (2) the total value of robustness is positive and significantly offsets the loss in welfare caused by disruption of the cross-radial link itself.